By forming a sole with a layer of fiber reinforcement coated with a matrix resin, i.e., a pre-preg, the rigidity of the sole is increased and the weight of the sole is reduced. The weight reduction of such a spike sole is important in football sports, or the like, as well as with track and field spike shoes.
It is well known to use a layer of the fiber reinforcement sheet to form a sole having spike pins (the first and second patent documents).